TireSizesFinder

215/50R15 vs 205/40R17

205/40R17 is 0.01 in (0.2 mm) shorter than 215/50R15, a −0.03% diameter difference. With the speedometer set for 215/50R15, an indicated 60 mph is 60.0 mph on 205/40R17.

Is this a safe swap?

Diameter difference −0.03%: under 1%

By overall diameter alone, 205/40R17 is a near match for 215/50R15; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 215/50R15 (23.46 in) vs 205/40R17 (23.46 in)215/50R1523.46 in × 8.46 in205/40R1723.46 in × 8.07 in
Side profile and tread width, drawn to the same scale.
215/50R15 vs 205/40R17 differences
Measurement215/50R15205/40R17Difference% diff
Overall diameter23.46 in (596.0 mm)23.46 in (595.8 mm)−0.01 in (−0.2 mm)−0.03%
Sidewall height4.23 in (107.5 mm)3.23 in (82.0 mm)−1.00 in (−25.5 mm)−23.72%
Section width8.46 in (215.0 mm)8.07 in (205.0 mm)−0.39 in (−10.0 mm)−4.65%
Circumference73.72 in (1,872.4 mm)73.69 in (1,871.8 mm)−0.02 in (−0.6 mm)−0.03%
Revolutions per mile8608600+0.03%
True speed with the speedometer calibrated for 215/50R15
IndicatedActual on 215/50R15Actual on 205/40R17Difference
30 mph30.0 mph30.0 mph0.0 mph
60 mph60.0 mph60.0 mph0.0 mph
75 mph75.0 mph75.0 mph0.0 mph

Ride-height change: 205/40R17 lowers the vehicle by 0.00 in (0.1 mm) at the axle (half the −0.2 mm diameter difference).

205/40R17 is 0.01 in shorter than 215/50R15 and 10 mm narrower, a 0.03% difference in overall diameter.

With the speedometer calibrated for 215/50R15, an indicated 60 mph is actually 60.0 mph on 205/40R17, and revolutions per mile change from 860 to 860.

205/40R17 mounts on a 17-inch wheel, a plus-2 fitment from the 15-inch wheel of 215/50R15.

Size pages

Other comparisons with 215/50R15

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Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.